One of Russia’s most prominent investigative journalists was arrested in the center of Moscow Thursday as he was on route to visit a source after police said they found illegal drugs in his backpack.

The independent news outlet Meduza, say that the police planted the drugs on their reporter, 36-year-old Ivan Golunov, as a way to shut down his reporting project about corruption in the city’s lucrative funeral industry that threatened to reveal links between prominent politicians and organized crime.

News of Golunov’s arrest only became public Friday as he was held incommunicado for over 12 hours, according to Meduza’s general director, who added that she has photos showing injuries that Golunov allegedly received while in police custody.

The Moscow City Police department denied both accusations.

Golunov’s friends launched online protests after investigators published photos allegedly taken inside the journalist’s apartment which police say suggests a large-scale drug operation was being run out of his living room, Alexander Urzhanov, a friend and the former chief editor of Russia’s NTV channel, responded with his own photos of Golunov’s apartment which do not appear to match those posted by police.

“We have evidence to suspect that Golunov is being chased because of his journalistic work,” Meduza wrote in a public statement. “We will find out who’s behind his persecution and will make this information public. We will defend our reporter by all means necessary.”